INRA is the French national institute for agronomic research. It carries on researches on Agriculture, Environment and Alimentation. Two Departments of INRA are particularly interested in agro-ecosystem studies: Environment & Agronomy, and Forest and Natural Ecosystems.
The INRA research unit on Grasslands (Ecophysiology and Genetic) is working on adaptation of plants to their environment, evolutionary processes of plant populations under different environmental constraints and management conditions, effects of grasslands on biogeochemical cycles, interactions and competitions among genotypes within grassland communities. An experimental unit is providing facilities for (i) an Observatory for Research on Environment on “The impacts of temporary grasslands within crop rotation on biogeochemical cycles, environmental fluxes and biodiversity” which is a part of the ORE “Agro-ecosystems, Biogeochemical Cycles and Biodiversity” network in France.

The Research Group of INRA Lusignan has developed a large scientific expertise on Plant Ecophysiology and Quantitative and Evolutionary Genetic for studying the functioning and evolution of grassland plant populations and communities under different environmental constraints such as drought, nutrition deficit and defoliation systems. The staff is well equipped in all the ecophysiology facilities allowing evaluation of dynamics of above and below ground primary production, photosynthesis and respiration, CO2 and N2O gaz exchanges, evapo-transpiration and soil water budget, plant mineral nutrition status, plant morphogenesis, interspecific competition. The Research Group has also expertise for intraspecific dynamic and genetic analysis through the use of molecular tools. Evolution of the intraspecific variability as well as the interspecific variability of grassland community according to environmental constraints is more particularly investigated. Resource sharing among individual plants within plant communities and competition is one of the more important expertises of the group. Expertises on soil organic matter dynamics and CO2 budget studies at field level have been developed for grassland ecosystems.